| This directory includes scripts and tools for setting up Flutter's continuous | |
| integration environments. | |
| ## Cirrus Linux | |
| Flutter's Linux tasks run on a custom Docker image. The `Dockerfile` for this | |
| image can be found at [/dev/ci/docker_linux/Dockerfile](https://github.com/flutter/flutter/blob/master/dev/ci/docker_linux/Dockerfile). | |
| On each new change to this `Dockerfile`, Cirrus will build a new version of | |
| the Docker image as a dependency to any Linux tests. It is no longer necessary | |
| to manually build and push the Docker image locally. | |
| There are some factors external to the actual `Dockerfile` that would | |
| necessitate rebuilding the Docker image, such as upstream code changes, (Linux | |
| distribution) repository updates or a file that gets `COPY`ied into the image | |
| changing. In this case, a trivial `Dockerfile` change (such as a comment) | |
| would invalidate the cache and trigger a rebuild. |